There is known a conventional speaker unit that is provided to be embedded in an interior member such as a door of a vehicle and includes a damping member provided on the backside of a diaphragm of a speaker to absorb a back pressure (for example, see International Publication Pamphlet No. WO2009/144818).
However, because the above conventional technology is required to install a damping member separately from a speaker, it is concerned that a speaker unit has a complicated configuration as a whole.